If you are thinking of using site-wide config files then you may want
to take a look at Template::Toolkit. It enables you to include
things like pre-loaded config files and also insert config files
into your site using the INCLUDE command.

Admittedly, Template::Toolkit is too complex for simple sites,
and I haven't had time to look at yours, but if you say you
are developing something for a large number of CGI programs
then it can be a real timesaver!